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More people around the world have nontuberculous mycobacteria (NTM) infections now than in the past. The infection most often comes from a type of NTM known as mycobacterium avium complex (MAC). MAC is often hard to get rid of. You’ll most likely need treatment for a year or more to cure it and it sometimes comes back. But your outlook depends on many factors. Here’s what you need to know.

How Does Diagnosis Affect My Outlook?

Generally, the earlier you get diagnosed with a MAC infection, the better you’ll do. But diagnosis often doesn’t happen right away. That’s because the infection can look like pneumonia or other lung conditions.

But once doctors realize that could be what you have, it’s possible to treat. The sooner this happens, the more likely it is that you’ll get the right treatment. You’ll also be more likely to have a good outcome.

If you’re worried you might have MAC, let your doctor know. Signs to watch for include:

  • Chronic fatigue
  • Night sweats
  • Trouble breathing or shortness of breath
  • Weight loss

You’re more likely to have MAC if you have other health conditions affecting your lungs or immune system. But anyone can get it. If you have these symptoms and they aren’t going away, see a doctor who specializes in diagnosing and treating lung conditions. A lung or infectious disease specialist also will have more experience treating MAC infections.

How Do Other Health Conditions Affect My Outlook?

Most people get exposed to the bacteria that cause MAC infections. You’re more likely to get sick from them if you have other health conditions. Your general health and other chronic conditions also will affect your outlook.

Some factors that may affect how you’ll do with treatment include other lung conditions such as:

  • Cystic fibrosis (CF)
  • Chronic obstructive pulmonary disease (COPD)
  • Pulmonary tuberculosis
  • Lung cancer

You’re also at more risk and may have a worse outlook with MAC infection if you have a weakened immune system due to conditions including:

  • Primary immune deficiency syndromes
  • AIDS
  • Blood cancers such as hairy cell leukemia

You also may be at greater risk for the infection and have a worse outlook if you’ve had a bone marrow, stem cell, or organ transplant. If you have other health conditions or have had a transplant, ask your doctor how this will affect your outlook with MAC.

What Other Factors Affect My Outlook?

Doctors often take other conditions and your symptoms into account when deciding to treat MAC. But some of those same factors also can affect your outlook. You may have a worse outlook if you have:

  • A fungal infection called aspergillosis in your lungs on top of the MAC
  • Cancer
  • Chronic heart disease
  • Chronic liver disease
  • Anemia
  • Old age
  • Obesity or a high body mass index (BMI)

Doctors may consider these factors when they choose to start treatment. But when you have other health conditions, you may not do as well even with treatment.

It’s a good idea to talk to your doctors about your outlook and what you should expect from treatment. Treatment can sometimes get rid of the infection for good. But treatment may also help to keep the infection stable even if it doesn’t go away. It may also help you with symptoms of the infection.

What Are the Mortality Rates for MAC?

One review of studies found that 1 in 4 people with MAC die within 5 years. But the cause of death wasn’t necessarily the infection itself, since many people with MAC have other health conditions, too. The risk also varies a lot from one study to the next.

Your risk of a poorer outcome may be greater if you:

  • Have nodules in your lungs (cavitary disease)
  • Have other health conditions
  • Are older
  • Are a man

Does the Strain Affect My Outlook?

Yes. Your outlook will depend on the specific bacteria causing your infection. MAC infections often don’t respond as well to antibiotics as other infections do. Your doctor may do tests to find out what type of bacteria is causing your infection. They may also do tests to see how well the bacteria responds to treatment with antibiotics.

If you treat the infection with one antibiotic, the bacteria causing your infection are more likely to develop resistance. Your outlook will improve if you take two or three antibiotics at once. It’s a good idea to see a specialist or other doctor with experience treating MAC to make sure you’re taking a combination of medicines that’s most likely to work. You’ll need to treat the infection for at least a year, and often longer, to be sure the infection is gone.

What if the Infection Comes Back?

Your doctor will consider the infection cured once there’s no sign of it for at least a year. But sometimes the infection goes away and then comes back. If that happens, it could mean that the infection wasn’t really gone. The bacteria may have developed resistance to treatment.

Some studies found that infection with MAC recurs up to 50% of the time. Most of the time that’s because of a new infection or reinfection. But it’s also possible to have a relapse if the bacteria are still there and bounce back after treatment ends. For some people, the infection can become chronic even with treatment.

What Can I Do to Improve My Outlook With MAC?

Even if you get rid of the infection, your lungs may still have lasting damage. But taking steps to care for your lungs and general health can help in your recovery and improve your outlook. Here are some tips to help you improve your chances of a good outcome:

  • See a lung or infectious disease specialist to make sure you’re on the right treatment course.
  • Follow your doctor’s advice and take your medicines as prescribed.
  • Ask your doctor about ways to clear mucus from your lungs. (Keeping your airways clear makes you less likely to get new infections on top of MAC.)
  • Washing your hands often and getting recommended vaccines also can help to keep you well.
  • Avoid smoke and other substances that could irritate your lungs.
  • Practice other healthy habits, including eating well and exercising.

Questions for Your Doctor

To stay on top of your infection, it helps to be informed. Here are some questions you may want to ask your doctor to make sure you’re doing all you can to improve your outlook:

  • What type of MAC do I have?
  • Do I need treatment? Why or why not?
  • What kind of treatment do I need?
  • Do I have choices to make about treatment?
  • What else can I do to help in my recovery?
  • Will I need surgery?
  • What are my chances of recovering?
  • What can I do to manage treatment side effects and stick with treatment?
  • Are there other risks?
  • What can I do to avoid a relapse?
  • What can I do to avoid getting reinfected?

Show Sources

Photo Credit: Thomas Barwick / Getty Images


Frontiers in Immunology: “The Rise of Non-Tuberculosis Mycobacterial Lung Disease.”

CHEST Foundation: “Nontuberculous Mycobacteria (NTM).”

European Respiratory Review: “Management of Mycobacterium avium complex and Mycobacterium abscessus pulmonary disease: therapeutic advances and emerging treatments.”

American Journal of Respiratory and Critical Care Medicine: “Prognostic factors of 634 HIV-negative patients with Mycobacterium avium complex lung disease.”

BMC Infectious Diseases: “High mortality in patients with Mycobacterium avium complex lung disease: a systematic review.”

American Lung Association: “NTM Lung Disease.”

Cleveland Clinic: “MAC Lung Disease.”